Plant tour: Gaining efficiencies in mechanical drives
Manufacturers need to seek ways to lower operating costs, energy use, and downtime; increase reliability and quality; and seek improvements throughout a product’s lifecycle. Also, look at the advantages of upgrades before parts wear out. Go to customers’ sites, and if you run into challenges, improve based on what you’ve learned.
These were bits of advices gleaned before, during, and after a March 22 Siemens Mechanical Drives plant tour in Elgin, Ill. Siemens Industry hosted a media event, where Aarnout Kant, general manager of the mechanical drives unit, and other experts offered advice. Peter Herzhoff and Jacob Schiff, mechanical drives plant managers for the Tollgate and Madeline plants, respectively, in Elgin, Ill., also offered advice for manufacturers, including the following.
– Listen to customers, visit their sites, and improve products and services throughout the product lifecycles. (Click here to see a video that explains how a screwdriver resulted in several design changes that reduced future downtime.)
– Simplify and integrate systems, cutting out components and even unneeded features where practical, to improve reliability and energy efficiency. In motion systems, fewer points of power transfer increase overall system efficiency. And an integrated system eliminates any possibility of finger-pointing in the rare case of a failure, adding customer confidence. Using 3-D modeling software speeds development.
– Look for features and functions that reduce downtime in the long term; though they may add to initial capital costs, they almost always result in a “yes” from end users interested in maximizing productivity.
– Use long-time employees with more experience to contribute, mentor, and teach younger team members.
– Ask plant-floor personnel for their ideas to improve safety, eliminate waste, and improve efficiency, and reward them for their efforts.
– Invest in local manufacturing expertise in ways that logistic costs and lower lead times for customers, which helps add market share. Use sensors to take critical measurements, and invest in new computers and new software to monitor and processes to keep quality high.
– Especially with expansions, renovations, and new plants, find ways to ensure products keep moving from design through manufacturing and shipping, limiting travel time and distance.
– Expand markets by adapting or scaling systems larger, when practical, to add efficiencies, and then seek new markets for those new designs. (Siemens found that wind gear units are very similar to those needed for the emerging market of tidal power generation. Taconite seals allow gear-reducing packages to be used in large-equipment mining applications.)
– Shift toward service or upgrades in mature markets and consider leaving or selling lower efficiency product lines. (Siemens sold its worm-drive business; helical or bevel helical gear designs offer 25%-30% greater efficiency.)
– Re-examine markets you left, because there might be good reasons to reinvest and return.
– Look for opportunities to add throughput and energy efficiencies with replacements. (A Siemens customer with a large concrete-crushing mill that’s worked since 1969, retrofit the gearbox in a higher-power upgrade.)
– For critical parts (in these plants, all are critical), track the origin, number the parts with serial numbers or data matrix codes, and inspect everything, at multiple stages of production. Ensure suppliers provide parts or materials that are tested. (Video shows a finished gear being tested for size with an automated machine that compensates for temperature. A difference of 1 F can translate into a 10-micrometer size difference.)
– Line up agreements from multiple suppliers, especially in tight markets like specialty steel, to lower lead times for customers.
– Use natural lighting where practical and retrofit to high-efficiency lighting, where high-efficiency tubular fluorescent (T5) lighting can be 50% more efficient than old T12 fixtures. [The Madeline plant was among the first manufacturing plants with LEED (Leadership in Energy and Environmental Design) certification, with attributes well beyond lighting, such as wise use of water—there are only two floor drains in the whole place, and those are for snow runoff from trucks that come inside.]
– Set up key metrics for each area of the plant, display them, and discuss anomalies (yellow or red, instead of green) daily—or more often, if needed. (Only one gear was found to be off-spec from grinding damage in 2.5 years, with throughput of more about 1,000 gears monthly, since start-up.) Light trees give visual cues on workcell status. Siemens uses the 5S strategy, among others. (5S is sort, simplify, shine, standardize, and sustain. Safety is often included for good measure.)
– Reconsider processes, even ones deemed efficient, when brought from other plants. (One process at the Madeline plant was reduced from 180 hours to 125, with local employee input.)
– Use models to help people remember strategies. The Siemens manufacturing strategy is represented by a house with a foundation, four pillars, and a roof. The foundation is people and continuous improvement, pillars are target and performance measurement (TPM), product lifecycle management (PLM), supply chain management (SCM), and customer relationship management (CRM), covered by a roof of production strategy.
– Take advantage of local and federal programs where it makes sense. (Local to the Siemens plants, the Elgin Chamber of Commerce promotes more efficient hiring by promoting a national career-readiness certificate.)
– Mark T. Hoske is CFE Media content manager, Control Engineering, Plant Engineering, Consulting-Specifying Engineer
Think Again: Improve Processes, Then Automate Think Again: Improve processes, then automate